What is the difference between divorce and annulment?

Although divorce and annulment both end a relationship, these two processes have significant differences.
With a divorce, the couple’s marriage was valid. The couple may seek a divorce on no-fault or fault-based grounds. Fault-based grounds for divorce in Texas are:
• Adultery
• Cruelty
• One spouse’s commission of a felony that requires imprisonment of at least one year.
• Abandonment by one spouse for a period of at least one year.
• Admission of one spouse to a mental hospital.
• Living separately and apart for three years.
In an annulment, the argument is that the marriage was never valid in the first place–it is null and void. Grounds for annulment in Texas include:
• One party was intoxicated at the time of the marriage and could not consent to the marriage.
• Duress, fraud, or force was used to induce one party into getting married.
• One of the parties was already married at the time of the marriage.
• The parties are related.
• One of the parties did not disclose that a divorce had been granted in the 30 days prior to the marriage.
• The marriage took place less than 72 hours after a marriage license was issued.
• One of the parties did not have the mental capacity to get married.
• One of the parties is impotent and did not disclose this fact to the other party.
• One of the parties was underage at the time of the marriage.
After both a divorce and an annulment, a judge may order child support and child custody. Parents are still under an obligation to support their children, even if the marriage was never valid in the first place.